Screen cloth anchoring and tensioning means



G. W. BEHNKE ET AL SCREEN CLOTH ANCHORING AND TENSIONING MEANS June 13,1950 3 Sheets-Sheet 1 Filed Jan. 13, 1947 INVENTORJ 6mm ATTORNEY June1950 e. w. BEHNKE ET AL SCREEN CLOTH ANCHORING AND TENSIONING MEANS 3Sheets-Sheet 2 Filed Jan. 15, 1947 INVENTORS a Mm.

A TTOR/VEY June 13, 1950 w, BEHNKE ET AL 2,511,239

SCREEN CLOTH ANCHORING AND TENSIONING MEANS Filed Jan. 13, 1947 3Sheets-Sheet 5 A T TORNE) Patented June 13, 1950 SCREEN CLOTH AN CHORINGAND TENSIONING MEANS George W. Behnke, Russell G. Westcott, and JohnSandula, Durand, Mich., assignors to Simplicity Engineering Company,Durand, Mich.

Application January 13, 1947, Serial No. 721,686

3 Claims.

This invention relates to screen anchoring and tensioning means forscreening machines, and more particularly to a screening machine forscreening fine food products and similar materials.

One of the prime objects of the invention is to design means foranchoring screen cloth of very fine mesh to the screen trays or frames,and without the use of bolts, rivets, or any other securing means Whichwould necessitate providing openings in the cloth.

Screen cloth of the nature described is capable of withstanding, for aconsiderable period of time, the severe stretch and. strains necessarywhen used for screening fine materials of all kinds, but when the clothis once ruptured by insertion of a bolt, rivet, welding, or any othermeans, it readily runs and tears, making replacement necessary with theresultant loss in time, materials and eificiency.

It is, therefore, one of the salient objects of the invention to providemeans engageable with the end sections of each screen strip, foruniformly and evenly gripping and anchoring the screen cloth at itsends, and to also provide means for continuously and automaticallytensioning the cloth.

Another object is to provide easily and quickly removable and insertablemeans, uniformly and evenly engageable over the entire width of the endsection of each screen cloth strip for clamping a relatively large areaof each section of said strip.

A further object is to provide simple, practical, and inexpensive meanswhereby the screen tension may be easily and quickly adjusted and held.

To the accomplishment of the foregoing and related ends, said inventionthen consists of the means hereinafter fully described and particularlypointed out in the appended claims, the annexed drawings and followingdescription se ting forth, in detail, eertain means and one mode ofcarrying out the invention, such disclosed means and mode illustrating,however, but one of various ways in which the principle of the inventionmay be used.

In the drawings:

Fig. 1 is an isometric view of a screening apparatus showing a pluralityof screen trays arranged in superimposed relation thereon.

Fig. 2 is an enlarged, isometric view showing a strip of screen clothwith the take-up bar and lock strip in position.

Fig. 3 is an enlarged, perspective view of the front take-up bar.

Fig. 4 is an enlarged, fragmentary, side-elevational view illustratingthe tray frame and spring take-up means.

Fig. 5 is a fragmentary, s-ide-elevational, diagrammatic view showingthe take-up bar and lock stri rolled over from the position shown inFig. 2.

Fig. 6 is a fragmentary, plan view of one of the tray frames, and

Fig. '7 is a side-elevational view thereof with the screen cloth inposition thereon.

Referring now more specifically to the drawings in which we have shownone embodiment of our invention: The numeral l0 indicates a fabricatedstructural frame havin bearings ll mounted thereon intermediate itslength, an eccentric or gyrating shaft 12 being journaled in saidbearings in the usual manner, and as fully described in Patent No.2,311,814, granted to us under date of February 23, 1943.

This frame In may be mounted on a suitable foundation, or it may besuspended from overhead supports (not shown), if desired, suitablebrackets l3 being provided on the corners of the frame to facilitatesuch suspension.

A gyratory frame G is mounted on the eccentric shaft l2 and is operablethereby, resilient corner supports B. being attached to the gymtoryframe and to the main frame Ill for yieldingly resisting movementthereof out of its normally balanced state, and for maintaining it inproper screening position, irrespective of load distribution and withoutin any manner interfering with the gyratory movement of the frame.

A plurality of individual tray members T are mounted on the gyratoryframe G in superimposed relation, and a sheet metal cover C fits overthe uppermost tray, said cover being formed with an intake spout l4through which the material to be Screened is fed to the machine.

Vertically disposed rods l5 are hingedly connected to brackets 16provided on the side walls of the gyratory frame by means of bolts l1,the upper threaded end of each rod extending through a slotted openingit formed in the brackets l9 provided on the side walls of the cover,and hand nuts 20 ar threaded on the upper threaded ends of the rods forrigidly securing the trays in assembled relation.

Each tray frame includes side bars 2| and a plurality of transverselydisposed cross bars 22 which are welded together so that th screencontacting areas are smooth and clean.

A cross bar 23 spans the front end of the frame, said bar beingreversely bent to form an overhanging lip 24, the opposite end of saidframe having a laterally projecting apron section A, the side walls 25of which project above and below the main frame, and a curved lip 26forms a part of said apron, said lip extending flush with the top of theframe, while the bottom wall forms a pan into which the material isdischarged from the screen.

In the application of the screen cloth S to the tray, it is essentialthat the screen cloth b cut absolutely square; it is then placed on asuitable frame, and each section is folded under as shown in Fig. 2 ofthe drawings, after which an elongated, smooth lock strip or bar 28 isinserted in each fold, and this fold with the lock strip in position, isthen placed in th channel 29 formed in the rear take-up bar B.

The take-up bar is then rolled over onto its reverse side (see Fig. ofthe drawings), and when tension is exerted on the strip, the screencloth will be firmly locked in position, the cloth being wrapped aroundthe lock strip withthe fre end of the cloth overlying the end of thetake-up bar so that the main body of the screen is stretched thereover,and does not come in direct contact with th edge of the screen frame.

With the screen cloth bottom face up, we then insert the feed end of thelock strip and folded screen cloth into the metal channel or groove 24provided on the front feed end of the frame; with the screen cloth inthis position we lay the remaining cloth on the frame top sid up, andthe take-up bar B is then in position for attachment at the dischargeend of the frame; we then attach the turned lip section 30 of thetake-up bar to the turned ends 3| of the tensioning members.

The tensioning means comprises a transversely disposed, preferablysquare shaft 32 which spans the apron A and projects through the sidewalls 25 thereof, a plurality or upwardly curved spring members 33 beingrigidly mounted thereon in spaced-apart relation, and th ends 3| of saidsprings being hook-shaped for easy engagement with the folded reverselybent lip section 39 of the take-up bar.

The ends of the shaft 32 are turned and threaded as at 34, these endsprojecting through the side walls 25 of the apron A, and nuts 35 serveto secure the shaft in set position.

When the screen S is placed on the frame, the turned ends SI of thesprings 33 engage the turned lip 39 of the take-up bar B, and when it isdesired to tension the screen, the shaft 32 is turned clockwise to bringthe screen to desired tension, and

it is there held until such time as it is desired to again tighten orremove the screen.

The manner of connecting the ends of the screen is of prime importancebecause of the nature of the cloth, as hereinbefore stated; it iscapable of considerable tension and wear excepting when the strands areshifted or broken to provide bolt or rivet holes, or when stretched oversharp edges, and in our method of anchoring, such disadvantages areeliminated, all contacting corners are rounded, the strain is evenlydistributed over the entire width of the cloth, and in addition, thegreater the pull, the tighter the screen cloth grips the lock strip, sothat the bearing on the free ends of the screen and frame is alsoenhanced.

The tensioning adjustment is extremely simple and easy to make, becausethe spring members 33 are resilient, the lock strip extends the entirewidth of the cloth, so there can be no blind spots or areas on thescreen.

From the foregoing description, it will be obvious that we haveperfected a very simple, practical, and effective screen cloth anchoringand tensioning means for screening machines and the like.

What we claim is:

1. In a screening apparatus, the combination of a frame having atransversely disposed, hookshaped section at the front end thereof, anda transversely-disposed apron-shaped section at the rear end, said apronbeing formed with vertical, end and bottom walls, a transverse,horizontally disposed, downwardly curved lip formed integral with thevertical wall and in alignment with and forming an extension of the topof the frame, a screen strip spanning said frame from end-to-end,take-up bars at the opposite ends of the screen strip and formed withopposed, hookshaped upper and lower sections, the lower section of thefront take-up bar re'lea'sably interlocking with the front hook-shapedsection of the frame, a lock bar loosely mounted in the upperhook-shaped section of said bar and around which one end of the screenstrip is wrapped with the end of the screen overlapping the end of theupper hook-shaped section for frictionally securing the free end betweensaid hook-shaped section and the main body of the screen strip, asimilar lock bar mounted in the upper section of the rear take-up barand around which the opposite end of the screen strip is wrapped withthe end of the screen overlapping the upper end of the upper section ofthe rear take-up bar and securing it between said section and the mainbody of the screen strip when the screen is tensioned, and adjustable,yieldable means connected to the lower hook-shaped section of the rearbar for tensioning said screen strip.

2. The combination defined in claim 1 in which a transversely disposedshaft spans the end walls of the apron on the rear of the frame, flat,bowed leaf spring member connected to said shaft and to the lowersection of the take-up bar, and means for rotatably adjusting said shaftto tension the screen strip.

3. The combination defined in claim 1 in which a transversely disposed,rotatably adjustable shaft is mounted in said apron and the yieldablemeans comprises transversely spaced leaf springs connected to the lowerend of the rear take-up bar and to said shaft for tensioning said screenstrip.

GEORGE W. BEHNKE. RUSSELL G. WES'ICOTT. JOHN SANDULA.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 780,826 Sneide Jan. 24, 19051,310,305 Smith July 15, 1919 1,332,685 Reynolds Mar. 2, 1920 1,353,549Sturtevant Sept. 21, 1920 1,713,143 Overstrom May 14, 1929 1,810,146Schollmeyer June 16, 1931 2,136,950 Overstrom Nov. 15, 1938 2,190,993Muir Feb. 20, 1940 2,338,523 Lincoln Jan. 4, 1944

